1. Field of the Invention
This invention relates to a material extraction device.
2. Description of the Related Art
Hazardous wastes may be temporarily stored in silos. Where such wastes are dry particulates, one known method of extraction is to pump water into the top of the silo and lower a centrifugal pump into the resulting slurry in order to raise the slurry. For certain particulate wastes, however, this approach is unacceptable since it is important that the wastes be kept dry. This is so with radioactive wastes because the addition of water would mobilise active isotopes and/or toxins greatly increasing the risk of their spread, including into the local water table.
The subject invention seeks to provide a material extraction device which may be used to extract dry particulate materials without any addition to or change of the state of that waste.